CA1216494A - Electrically actuated valve assembly - Google Patents
Electrically actuated valve assemblyInfo
- Publication number
- CA1216494A CA1216494A CA000466595A CA466595A CA1216494A CA 1216494 A CA1216494 A CA 1216494A CA 000466595 A CA000466595 A CA 000466595A CA 466595 A CA466595 A CA 466595A CA 1216494 A CA1216494 A CA 1216494A
- Authority
- CA
- Canada
- Prior art keywords
- armature
- pole piece
- pilot
- valve
- guide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K31/00—Actuating devices; Operating means; Releasing devices
- F16K31/12—Actuating devices; Operating means; Releasing devices actuated by fluid
- F16K31/36—Actuating devices; Operating means; Releasing devices actuated by fluid in which fluid from the circuit is constantly supplied to the fluid motor
- F16K31/40—Actuating devices; Operating means; Releasing devices actuated by fluid in which fluid from the circuit is constantly supplied to the fluid motor with electrically-actuated member in the discharge of the motor
- F16K31/402—Actuating devices; Operating means; Releasing devices actuated by fluid in which fluid from the circuit is constantly supplied to the fluid motor with electrically-actuated member in the discharge of the motor acting on a diaphragm
- F16K31/404—Actuating devices; Operating means; Releasing devices actuated by fluid in which fluid from the circuit is constantly supplied to the fluid motor with electrically-actuated member in the discharge of the motor acting on a diaphragm the discharge being effected through the diaphragm and being blockable by an electrically-actuated member making contact with the diaphragm
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Magnetically Actuated Valves (AREA)
Abstract
ABSTRACT
A pilot operated solenoid actuated valve assembly having a differential pressure sensing diaphragm for opening the main valve in response to loss of pressure through a pilot flow valve from a control pressure chamber. The pilot valve-armature is housed in a non-magnetic guide which is sealed about the diaphragm to form the control pressure chamber. Tubular pole segments surround the guide and define a magnetic air gap. An auxiliary pole piece is loosely received in the guide and is spring biased away from the armature. The pole piece enables the armature to be held fully open at a substantially reduced level of voltage from the actuation or service voltage.
A pilot operated solenoid actuated valve assembly having a differential pressure sensing diaphragm for opening the main valve in response to loss of pressure through a pilot flow valve from a control pressure chamber. The pilot valve-armature is housed in a non-magnetic guide which is sealed about the diaphragm to form the control pressure chamber. Tubular pole segments surround the guide and define a magnetic air gap. An auxiliary pole piece is loosely received in the guide and is spring biased away from the armature. The pole piece enables the armature to be held fully open at a substantially reduced level of voltage from the actuation or service voltage.
Description
ELECTRICALLY ACTUATED VALVE ASSEMBLY
BACKGROUND OF THE INVENTION
The present invention relates to electrically actuated valves of the type employed for control of 5 water inlet flow to appliances, as for example, domestic dish washers and washing machines. In order to prevent overheating of the electrical actuator, it has been required to energize the water inlet valve with a very minimum of electrial power.
It has, however, been desired to eliminate the electro-mechanical programmer and to provide electronic control of the appliance program functions utilizing low voltage solid state control devices. Such electronic control requires the water inlet valve to actuate when supplied with a direct current, which may be filtered, fullwave or halfwave rectified voltage in the ranye 3-120 volts and to consume only about 4 watts of power.
The aforesaid low power requirements for an appliance inlet valve are considered quite stringent when compared to the requirements for valve employed in appliances controlled by an electromechanical programmer switching mechanism.
In order to keep the electrical power requirement for appliance inlet valves actuation reduced ~5 to a minimum, it has been the practice to employ a solenoid powered armature-pilot valve for initiating actuation of the main inlet valve. Such an arrangement requires only a small magnetomotive force from the solenoid to move the armature for opening the pilot ,0 valve. The use of a low opening force pilot operated valve has enabled the power reguirements for the solenoid to be minimiæed; and, thus~ this type of valve
BACKGROUND OF THE INVENTION
The present invention relates to electrically actuated valves of the type employed for control of 5 water inlet flow to appliances, as for example, domestic dish washers and washing machines. In order to prevent overheating of the electrical actuator, it has been required to energize the water inlet valve with a very minimum of electrial power.
It has, however, been desired to eliminate the electro-mechanical programmer and to provide electronic control of the appliance program functions utilizing low voltage solid state control devices. Such electronic control requires the water inlet valve to actuate when supplied with a direct current, which may be filtered, fullwave or halfwave rectified voltage in the ranye 3-120 volts and to consume only about 4 watts of power.
The aforesaid low power requirements for an appliance inlet valve are considered quite stringent when compared to the requirements for valve employed in appliances controlled by an electromechanical programmer switching mechanism.
In order to keep the electrical power requirement for appliance inlet valves actuation reduced ~5 to a minimum, it has been the practice to employ a solenoid powered armature-pilot valve for initiating actuation of the main inlet valve. Such an arrangement requires only a small magnetomotive force from the solenoid to move the armature for opening the pilot ,0 valve. The use of a low opening force pilot operated valve has enabled the power reguirements for the solenoid to be minimiæed; and, thus~ this type of valve
-2 has been widely used in domestic washing appliance applications. Typically, in such a valve opening the pilot valve permits pilot flow to the outlet from a control pressure chamber thereby creating a pressure differential across a diaphragm connected to the main valve, whereupon the pressure differential opens the main valve.
It has thus been desired to provide an electrically energized pilot operated water inlet valve for appliances capable of operation from a direct current power source having a very low power consumption therefrom.
SUMMARY OF THE INVENTION
_ The present invention provides an electrically energi7ed pilot operated solenoid valve suitable for very low power direct current voltage controlled systems such as solid state electronic switching for the control of water inlet flow to a domestic washing appliances.
The present invention provides a novel solution to the above described problem of providing an electrically operated valve, low in manufacturing cost, and capable of energization by a direct current voltage and low power consumption in the range of about 4 watts for such a low voltage supply.
The present invention employs the well known armature-pilot valve operator which, upon energization of the solenoid, enables a pilot flow for creating a pressure differential across a diaphragm to open the mai~ valve operator~ The armature-pilot valve of the present invention is received in a non-magnetic armature guide which is sealed about the periphery of the diaphragm to provide a control pressure chamber from which pilot flow is initiated for creating the differential pressure which opens the main valve.
The non-magnetic armature guide has received thereover axially spaced ferromagnetic tubular pole pieces which define magnetically opposite poles having an air gap disposed therebetween. The armature is received in the guide having a pilot valve on one end with the other end disposed adjacent the air gap formed by the tubular pole pieces. An auxiliary stationary ferromagnetic pole piece is received in the armature guide and is biased against the closed end thereof by one end of a spring the other end of which urges the armature-pilot in the opposite direction to close the pilot flow valve.
The unique solenoid construction of the present invention thus employs an auxiliary stationary pole piece disposed within the armature guide, and thus within the c:ontrol pressure chamber, for concentrating magnetic flux to increase the magnetomotive force acting on the armature for moving the armature to the fully opened position contacting the auxiliary pole piece and for preventing oscillation. The auxiliary pole piece is disposed remote from the magnetic pole air gap so as not to interfere with the attractions of the armature to the gap between the poles.
The unique solenoid construction of the present valve enables the magnetic pole segments in the form of the axially spaced tubular coil cores to be arranged so as to permit a shorter axial air gap between the poles than would be required for a construction not employing the arrangement of the present invention.
The unique valve construction of the present invention permits a solenoid energized valve to be operated on a D.C. power supply, filtered or unfiltered and draws a minimum of current therefrom for controlling inlet flow to an appliance. The unique valve construction of the present invention employs an auxiliary ferromagnetic pole piece disposed in the control pressure chamber for the pilot valve to provide a concen~ration of magnetic flux for holding the pilot 5 armature in a fully open position and preventing oscillation. The unique valve construction of the present invention enables the electrically energized pilot operated valve to remain in the fully open position with a reduced voltage applied to the valve 10 after it has moved to the fully open position.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a cross section of a dual coil appliance inlet mixing valve employing the present invention;
Figure 2 is an enlarged view of one coil of the valve of Figure 1 shown in the energized valve closed condition; and, Figure 3 is a view similar to Figure 2 illustrating the valve in the coil energized open 20 condition.
Figure 4 is a view similar to Figure 2 illustrating an alternate embodiment of the armature and pole piece.
Detailed Description Referring now to Figure 1, a dual coil valve indicated generally at 10 is shown as having a pair of valve coil assemblies indicated generally at 12 and 14 and hydraulically series connected for controlling water flow to an appliance. The inlet is indicated generally 30 at 16 in Figure 1 with the outlet indicated generally at 18.
The coil assemblies 12, 14 are adapted for connection to a source of electrical power through electrical connecting terminals indicated respectively ~2 ~
at 20, 22. In the presently preferred practice, coil assemblies 12 and 14 are suitable for ~nergization by a direct current source haviny a voltage in the range 12-24 volts and each o~ the coil assemblies is rated at 4 wat~s at 24 volts D.C. ~owever, it will be understood that the coil assemblies 12, 14 may be employed in control systems utilizing alternating current power source having voltages and wattages in excess of the preferred range.
Referring now to Figure 2, the coil assembly 14 is shown as retained on the valve body or housing 20 by a suitable pole frame, formed of ferromagnetic material, which has a pair of spaced flanges 23 connected for providing a continuous ferromagnetic flux path 15 therebetween. Upper an~ lower ferromagnetic tubular pole pieces 24~ 26 respectively are received respectively in the flanges and are disposed with the ends thereof defining opposite maynetic poles defining an air gap indicated at "D".
The coil assembly 14 has a plurality of turns of suitable electrical conductor 28/ preferably magnet wire which terrninates in leads (not shown) connected to the electrical terminals 22 (see Fig. 1).
The body means 20 has a main valving chamber 30 which communicates via passage 32 with the valve inlet 16 and defines therein a main valve seat 34, which surrounds an outlet passage 36.
A pressure responsive diaphragm 38, preferably
It has thus been desired to provide an electrically energized pilot operated water inlet valve for appliances capable of operation from a direct current power source having a very low power consumption therefrom.
SUMMARY OF THE INVENTION
_ The present invention provides an electrically energi7ed pilot operated solenoid valve suitable for very low power direct current voltage controlled systems such as solid state electronic switching for the control of water inlet flow to a domestic washing appliances.
The present invention provides a novel solution to the above described problem of providing an electrically operated valve, low in manufacturing cost, and capable of energization by a direct current voltage and low power consumption in the range of about 4 watts for such a low voltage supply.
The present invention employs the well known armature-pilot valve operator which, upon energization of the solenoid, enables a pilot flow for creating a pressure differential across a diaphragm to open the mai~ valve operator~ The armature-pilot valve of the present invention is received in a non-magnetic armature guide which is sealed about the periphery of the diaphragm to provide a control pressure chamber from which pilot flow is initiated for creating the differential pressure which opens the main valve.
The non-magnetic armature guide has received thereover axially spaced ferromagnetic tubular pole pieces which define magnetically opposite poles having an air gap disposed therebetween. The armature is received in the guide having a pilot valve on one end with the other end disposed adjacent the air gap formed by the tubular pole pieces. An auxiliary stationary ferromagnetic pole piece is received in the armature guide and is biased against the closed end thereof by one end of a spring the other end of which urges the armature-pilot in the opposite direction to close the pilot flow valve.
The unique solenoid construction of the present invention thus employs an auxiliary stationary pole piece disposed within the armature guide, and thus within the c:ontrol pressure chamber, for concentrating magnetic flux to increase the magnetomotive force acting on the armature for moving the armature to the fully opened position contacting the auxiliary pole piece and for preventing oscillation. The auxiliary pole piece is disposed remote from the magnetic pole air gap so as not to interfere with the attractions of the armature to the gap between the poles.
The unique solenoid construction of the present valve enables the magnetic pole segments in the form of the axially spaced tubular coil cores to be arranged so as to permit a shorter axial air gap between the poles than would be required for a construction not employing the arrangement of the present invention.
The unique valve construction of the present invention permits a solenoid energized valve to be operated on a D.C. power supply, filtered or unfiltered and draws a minimum of current therefrom for controlling inlet flow to an appliance. The unique valve construction of the present invention employs an auxiliary ferromagnetic pole piece disposed in the control pressure chamber for the pilot valve to provide a concen~ration of magnetic flux for holding the pilot 5 armature in a fully open position and preventing oscillation. The unique valve construction of the present invention enables the electrically energized pilot operated valve to remain in the fully open position with a reduced voltage applied to the valve 10 after it has moved to the fully open position.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a cross section of a dual coil appliance inlet mixing valve employing the present invention;
Figure 2 is an enlarged view of one coil of the valve of Figure 1 shown in the energized valve closed condition; and, Figure 3 is a view similar to Figure 2 illustrating the valve in the coil energized open 20 condition.
Figure 4 is a view similar to Figure 2 illustrating an alternate embodiment of the armature and pole piece.
Detailed Description Referring now to Figure 1, a dual coil valve indicated generally at 10 is shown as having a pair of valve coil assemblies indicated generally at 12 and 14 and hydraulically series connected for controlling water flow to an appliance. The inlet is indicated generally 30 at 16 in Figure 1 with the outlet indicated generally at 18.
The coil assemblies 12, 14 are adapted for connection to a source of electrical power through electrical connecting terminals indicated respectively ~2 ~
at 20, 22. In the presently preferred practice, coil assemblies 12 and 14 are suitable for ~nergization by a direct current source haviny a voltage in the range 12-24 volts and each o~ the coil assemblies is rated at 4 wat~s at 24 volts D.C. ~owever, it will be understood that the coil assemblies 12, 14 may be employed in control systems utilizing alternating current power source having voltages and wattages in excess of the preferred range.
Referring now to Figure 2, the coil assembly 14 is shown as retained on the valve body or housing 20 by a suitable pole frame, formed of ferromagnetic material, which has a pair of spaced flanges 23 connected for providing a continuous ferromagnetic flux path 15 therebetween. Upper an~ lower ferromagnetic tubular pole pieces 24~ 26 respectively are received respectively in the flanges and are disposed with the ends thereof defining opposite maynetic poles defining an air gap indicated at "D".
The coil assembly 14 has a plurality of turns of suitable electrical conductor 28/ preferably magnet wire which terrninates in leads (not shown) connected to the electrical terminals 22 (see Fig. 1).
The body means 20 has a main valving chamber 30 which communicates via passage 32 with the valve inlet 16 and defines therein a main valve seat 34, which surrounds an outlet passage 36.
A pressure responsive diaphragm 38, preferably
3~ formed of elastomeric material, has a sealing rim 40 provided about the outer periphery thereof and registered in sealing engagement with an annular lips 42 provided in the valving chamber. Diaphragm 38 has the central portion thereof thickened to provide a main 35 valving member 44 for moveably contacting valve seat 34 and is shown in Figure 2 in solid outline in the closed position contacting seat 34. In the closed position illustrated in Figure 2, fluid flow between chamber 30 and outlet 36 is prevented by the sealing of main valve member 44 against the seat 34.
With continuing reference to Figure 2, the valve member 44, comprising the central portion in diaphragm 38, has received therethrough a suitable insert 46 which extends into the outlet passage 36 for sliding engagement with the wall thereof to thus act as a guide for movement of the valve 44. Insert 46 has the outer periphery thereof engaging the surface of the diaphragm at annular rib 47 for sealing thereabout and preventing fluid passage between the insert and the diaphragm about the periperhy of the insert.
Diaphragm insert 46 has a pilot passage 48 formed therethrough and terminating at the upper surface of the insert in a pilot valve seat sur~ace 50.
A guide means 52, formed of non-metallic material, has a cylindrical tubular upper section received in the tubular pole pieces 24, 26 with a closed upper end 54 defining therein a guide hollow 56 which communicates with a larger diameter hollow 58 formed in the lower portion of the guide means 52. The lower portion of guide means 52 has the outer periphery thereof formed in an annular lip 60 which is received over the outer rim 40 of the diaphragm in fluid pressure sealing engagement and cooperates with a bore 62 provided in the body means 80 for positioning the diaphragm therein.
The guide means 52 is thus disposed such that in cooperation with diaphragm 38, the upper and lower guide means hollow portions 56, 58 define a fluid pressure control chamber necessary for proper function and operation of the valve as will be hereinafter described.
With reference to Figure 2, an armature means 5 is received within the upper guide hollow 56 and includes a generally cylindrical member 64 formed of ferromagnetic material and slideably disposed in the guide hollow 56 for movement therein. The lower portion of armature member 64 has received therein a pilot 10 valving member 66 preferably formed of suitable elastomeric material for valving contact with pilot valve seat 50~ In Figure 2, the armature is shown in the downward limit position of its movement in the closed position with pilot valve member 66 contacting 15 pilot valve seat 5Q for preventing fluid flow from the control chamber through passage 48.
The upper end of the armature member 64 preferably has a reduced diameter stepped portion thereon. The upper end of the larger diameter portion 20 of the armature member 64 is disposed generally axially in the middle of the air gap denoted by "D".
An auxiliary pole piece means 68 is slideably received in the upper guide hollow 56 and is formed of 25 suitable ferromagnetic material. The auxiliary pole piece 68 has registered thereagainst the upper end of a suitable spring means 70, which has the lower end thereof received over the smaller diameter portion of the armature 64. The spring 70 biases the auxiliary 30 pole piece 68 upwardly into contact with the closed end portion 54 of the guide. The lower end of the spring urges armature member 64 downwardly to thereby cause pilot valve member 66 to be seat:ed on pilot valve seat 50. The arrangement of the auxiliary pole piece 68 ~ 2~L6~
within the guide member 52 permits assembly of the auxiliary pole piece, spring and armature into the guide hollow 56 and subsequent assembly of the diaphragm into the lip 60 as a subassembly to provide ease of installation into the body means 20.
In the presently preferred practice of the invention the auxiliary pole piece 68 is located so as to be remote from the pole piece air gap "D" such that upon flow of electrical current in conductor 28, the 10 concentration of magnetic flux at air gap "D" causes a sufficient magnetomotive force on armature member 64 and results in upward movement of the armature. In the present practice of the invention, a ten percent increase in magnetomotive force has been readily 15 obtained. Upon the armature moving upward in response to magnetomotive force, the upward limit of travel of the armature is provided by the upper end of the armature member 64 contacting the auxiliary pole piece 68 and results in a strong magnetic attraction 20 therebetween and tends to reduce oscillation. Once the armature member 64 contacts the auxiliary pole piece 68, ~he voltage applied to the coil may be significantly reduced without causing loss of magnetomotive attraction 25 between the auxiliary pole piece 68 and the armature 64. Thus the "hold-inl' voltage for maintaining the armature in the fully open position is substantially less than the rated or service voltage applied to the coil for initial actuation.
Referring now to Figure 3. The control pressure chamber is initially supplied through bleed holes 72, 74 provided respectively in the valve member 44 and the insert 46. The bleed holes are sized so as to provide pressurizaton of the control chamber 35 initially from the fluid inlet. Upon opening of the - ~ -pilot valve passage 48 fluid flows to the outlet from the control pressure chamber reducing the pressure therein and causing the pressure in valving chamber 30 to lift the diaphragm and main member 44 upwardly to open the valve to the position shown in Figure 3.
In the presently preferred practice of the invention, ~he arrangment of the electromagnetic valve shown in Figures 2 and 3 employing auxiliary pole piece 68 permits the air gap "D" to be reduced to a value approximately 80% of that of the gap required to provide the required armature travel as compared with a valve construction not employing the auxiliary pole piece means 68 of the present invention. The resulting arrangement of the present invention provides an electromagnetically actuated valve which will open at a voltage of about 60~ of that required for openiny of a corresponding valve not employing the present invention. In the presently preferred practice of the invention, for a 24 volt fullwave rectified D.C. supply, the valve is operable with the air gap "D" having a value of 0.180 inches (4.6 millimeters)O
The valve of the present invention in the preferred practice has the ratio of the mass of the auxiliary pole piece means 68 to the mass of armature member 64 chosen in the range 45~50%. With this arrangement a valve operable for ac-tuation on a direct current supply at 24 volts will maintain the armature in the fully open position as showr. in Figure 3 when the supply voltage is dropped to a level of 10 volts; and, will maintain the armature in such position until the voltage falls below the 10 volt level.
Referring now to figure 4, another embodiment of the invention is illustrated in which a non-magnetic disc or thin-plate member 72 is disposed between auxiliary pole piece 68 and armature 64. The disc 72 is ~6~
--] o -formed of non-magnetic material, prefera~ly stainless steel, and serves to reduce to a negligible value the effects of residual magnetism in the auxiliary pole piece and armature which could cause the armature to be 5 captured in the open position when the coil is de-energized. The disc 72 is generally thin with respect to its diameter, having in the preferred practice a thickness on the order of three percent of the diameter thereof.
The valve of the present invention thus employs the unique electromagnetic actuation means hàving a stationary auxiliary pole piece means disposed within the sealed control pressure chamber for enabling actuation o:E the pilot valve at a lower voltage and 15 making contact with the armature for holdings of the pilot valve in the open position at a substantially reduced voltage level.
The present invention provides an electrically energized, pilot operated valve assembly which is 20 suitable for lower power energization by a low voltage power supply. The valve of the present invention employs a stationary auxiliary pole piece means within the fluid pressure control chamber for concentrating 25 therein electromagnetic flux to make contact with and hold the armature in the fully open position despite reduced levels o voltage in the power supply. The present invention provides an electrically actuated pilot operated low power valve particulary suitable for 30 application in appliances such as domestic washing machines.
Although the invention has hereinabove been described with respect to the preferred practice, it will be understood by those skilled in the art, that the 35 invention is capable of modification and variation and is limited only by the following claims.
With continuing reference to Figure 2, the valve member 44, comprising the central portion in diaphragm 38, has received therethrough a suitable insert 46 which extends into the outlet passage 36 for sliding engagement with the wall thereof to thus act as a guide for movement of the valve 44. Insert 46 has the outer periphery thereof engaging the surface of the diaphragm at annular rib 47 for sealing thereabout and preventing fluid passage between the insert and the diaphragm about the periperhy of the insert.
Diaphragm insert 46 has a pilot passage 48 formed therethrough and terminating at the upper surface of the insert in a pilot valve seat sur~ace 50.
A guide means 52, formed of non-metallic material, has a cylindrical tubular upper section received in the tubular pole pieces 24, 26 with a closed upper end 54 defining therein a guide hollow 56 which communicates with a larger diameter hollow 58 formed in the lower portion of the guide means 52. The lower portion of guide means 52 has the outer periphery thereof formed in an annular lip 60 which is received over the outer rim 40 of the diaphragm in fluid pressure sealing engagement and cooperates with a bore 62 provided in the body means 80 for positioning the diaphragm therein.
The guide means 52 is thus disposed such that in cooperation with diaphragm 38, the upper and lower guide means hollow portions 56, 58 define a fluid pressure control chamber necessary for proper function and operation of the valve as will be hereinafter described.
With reference to Figure 2, an armature means 5 is received within the upper guide hollow 56 and includes a generally cylindrical member 64 formed of ferromagnetic material and slideably disposed in the guide hollow 56 for movement therein. The lower portion of armature member 64 has received therein a pilot 10 valving member 66 preferably formed of suitable elastomeric material for valving contact with pilot valve seat 50~ In Figure 2, the armature is shown in the downward limit position of its movement in the closed position with pilot valve member 66 contacting 15 pilot valve seat 5Q for preventing fluid flow from the control chamber through passage 48.
The upper end of the armature member 64 preferably has a reduced diameter stepped portion thereon. The upper end of the larger diameter portion 20 of the armature member 64 is disposed generally axially in the middle of the air gap denoted by "D".
An auxiliary pole piece means 68 is slideably received in the upper guide hollow 56 and is formed of 25 suitable ferromagnetic material. The auxiliary pole piece 68 has registered thereagainst the upper end of a suitable spring means 70, which has the lower end thereof received over the smaller diameter portion of the armature 64. The spring 70 biases the auxiliary 30 pole piece 68 upwardly into contact with the closed end portion 54 of the guide. The lower end of the spring urges armature member 64 downwardly to thereby cause pilot valve member 66 to be seat:ed on pilot valve seat 50. The arrangement of the auxiliary pole piece 68 ~ 2~L6~
within the guide member 52 permits assembly of the auxiliary pole piece, spring and armature into the guide hollow 56 and subsequent assembly of the diaphragm into the lip 60 as a subassembly to provide ease of installation into the body means 20.
In the presently preferred practice of the invention the auxiliary pole piece 68 is located so as to be remote from the pole piece air gap "D" such that upon flow of electrical current in conductor 28, the 10 concentration of magnetic flux at air gap "D" causes a sufficient magnetomotive force on armature member 64 and results in upward movement of the armature. In the present practice of the invention, a ten percent increase in magnetomotive force has been readily 15 obtained. Upon the armature moving upward in response to magnetomotive force, the upward limit of travel of the armature is provided by the upper end of the armature member 64 contacting the auxiliary pole piece 68 and results in a strong magnetic attraction 20 therebetween and tends to reduce oscillation. Once the armature member 64 contacts the auxiliary pole piece 68, ~he voltage applied to the coil may be significantly reduced without causing loss of magnetomotive attraction 25 between the auxiliary pole piece 68 and the armature 64. Thus the "hold-inl' voltage for maintaining the armature in the fully open position is substantially less than the rated or service voltage applied to the coil for initial actuation.
Referring now to Figure 3. The control pressure chamber is initially supplied through bleed holes 72, 74 provided respectively in the valve member 44 and the insert 46. The bleed holes are sized so as to provide pressurizaton of the control chamber 35 initially from the fluid inlet. Upon opening of the - ~ -pilot valve passage 48 fluid flows to the outlet from the control pressure chamber reducing the pressure therein and causing the pressure in valving chamber 30 to lift the diaphragm and main member 44 upwardly to open the valve to the position shown in Figure 3.
In the presently preferred practice of the invention, ~he arrangment of the electromagnetic valve shown in Figures 2 and 3 employing auxiliary pole piece 68 permits the air gap "D" to be reduced to a value approximately 80% of that of the gap required to provide the required armature travel as compared with a valve construction not employing the auxiliary pole piece means 68 of the present invention. The resulting arrangement of the present invention provides an electromagnetically actuated valve which will open at a voltage of about 60~ of that required for openiny of a corresponding valve not employing the present invention. In the presently preferred practice of the invention, for a 24 volt fullwave rectified D.C. supply, the valve is operable with the air gap "D" having a value of 0.180 inches (4.6 millimeters)O
The valve of the present invention in the preferred practice has the ratio of the mass of the auxiliary pole piece means 68 to the mass of armature member 64 chosen in the range 45~50%. With this arrangement a valve operable for ac-tuation on a direct current supply at 24 volts will maintain the armature in the fully open position as showr. in Figure 3 when the supply voltage is dropped to a level of 10 volts; and, will maintain the armature in such position until the voltage falls below the 10 volt level.
Referring now to figure 4, another embodiment of the invention is illustrated in which a non-magnetic disc or thin-plate member 72 is disposed between auxiliary pole piece 68 and armature 64. The disc 72 is ~6~
--] o -formed of non-magnetic material, prefera~ly stainless steel, and serves to reduce to a negligible value the effects of residual magnetism in the auxiliary pole piece and armature which could cause the armature to be 5 captured in the open position when the coil is de-energized. The disc 72 is generally thin with respect to its diameter, having in the preferred practice a thickness on the order of three percent of the diameter thereof.
The valve of the present invention thus employs the unique electromagnetic actuation means hàving a stationary auxiliary pole piece means disposed within the sealed control pressure chamber for enabling actuation o:E the pilot valve at a lower voltage and 15 making contact with the armature for holdings of the pilot valve in the open position at a substantially reduced voltage level.
The present invention provides an electrically energized, pilot operated valve assembly which is 20 suitable for lower power energization by a low voltage power supply. The valve of the present invention employs a stationary auxiliary pole piece means within the fluid pressure control chamber for concentrating 25 therein electromagnetic flux to make contact with and hold the armature in the fully open position despite reduced levels o voltage in the power supply. The present invention provides an electrically actuated pilot operated low power valve particulary suitable for 30 application in appliances such as domestic washing machines.
Although the invention has hereinabove been described with respect to the preferred practice, it will be understood by those skilled in the art, that the 35 invention is capable of modification and variation and is limited only by the following claims.
Claims (7)
- Claim 1. An electrically energized pilot operated fluid flow valve assembly comprising:
(a) a coil of electrically conductive material;
(b) a pair of tubular pole pieces formed of ferromagnetic material received centrally within said coil, said pole pieces disposed in axially spaced arrangement to define therebetween an air gap;
(c) armature guide means, formed of non-metallic material received within said tubular pole pieces and defining therein a fluid pressre sealing hollow with one end closed and disposed adjacent an end of said tubular pole pieces remote from said air gap, with the opposite end of said guide defining an open end with the periphery thereof enlarged from the diameter of said tubular pole pieces;
(d) diaphragm means sealed about the said periphery of said guide to form in cooperation therewith a fluid sealing chamber within said guide, said diaphragm including means defining a pilot flow passage therethrough communicating with said chamber and a pilot valve seat for said passage disposed within said chamber;
(e) auxiliary stationary pole piece means disposed within said guide and registered against said closed end thereof;
(f) armature means including a member of ferromagnetic means moveably received in said guide for axial movement with respect to said air gap; said armature having one end disposed for contacting said auxiliary pole piece and the opposite end including means defining a pilot valve for sealing against said pilot valve seat;
(g) spring means having one reacting surface thereof contacting said auxiliary pole piece and the opposite reacting surface thereof contacting said armature means for biasing said auxiliary pole piece and said armature means in opposite directions, wherein said pole piece is urged against said closed end of said guide and said pilot valve is urged against said pilot valve seat;
(h) means defining a main valving surface on said diaphragm portions thereof external to said chamber;
(i) housing means defining a valve inlet passage and having said coil and guide received thereon, said housing means defining a main valve seat disposed for sealing contact with said main valving surface and communicating with a valve outlet passage; and means defining a bleed passage connecting said inlet passage and said chamber continuously for limited fluid communication therebetween. - Claim 2. The valve assembly defined in claim 1, wherein, said auxiliary pole piece and said armature each have an annular shoulder thereon, with respectively one reacting surface of said spring means registered thereagainst.
- Claim 3. The valve assembly defined in claim 1, wherein, said auxiliary pole piece has an axial length substantially less than the length of said armature means.
- Claim 4. The valve assembly defined in claim 1, wherein said tubular pole pieces are disposed to position said air gap adjacent one end of said armature means and said spring means in the valve de-energized condition, biases said armature means to a position spaced from said auxiliary pole piece means.
- Claim 5. The valve assembly defined in claim 1, wherein said auxiliary pole piece means is slideably received in said armature guide means and held in registration with the closed end thereof under the urging of said spring means.
- Claim 6. The valve assembly defined in claim 1, wherein the ratio of mass of the pole piece means to the armature means is in the range 45-50% whereby the voltage required to hold said armature in the fully actuated position comprises about 40% of the rated or applied service voltage of said coil.
- Claim 7. An electrically energized pilot operated fluid flow valve assembly comprising:
(a) body means defining an inlet passage adapted for receiving fluid flow therein, an outlet passage for discharging fluid flow and a main valve seat disposed in the flow path between said inlet and outlet;
(b) pressure responsive means, including a main valve member moveable in response to differential pressure between a closed position contacting said valve set for blocking flow to said outlet passage and an open position permitting full flow to said outlet passage;
(c) guide means received on said body means including a member formed of non-metallic material defining a closed end hollow and defining, in cooperation with said pressure responsive means, a fluid pressure control chamber;
(d) said pressure responsive means including means defining a pilot flow passage communicating said control pressure chamber with said outlet passage and a pilot passage seat disposed in the flow path of said pilot passage;
(e) armature means including a member formed of ferromagnetic material slideably received in said guide means hollow and having a pilot valving surface, said armature means movable between a closed position in which said pilot valving surface contacts said pilot valve seat for blocking flow through said pilot passage and an open positin in which flow is permitted through said pilot passage;
(f) an auxiliary stationary pole piece including a member formed of ferromagnetic material received in said hollow and disposed at the closed end thereof;
(g) tubular pole piece means including a first and second generally tubular member formed of ferromagnetic material and disposed about said guide hollow, said tubular members defining axially opposite magnetic poles and an air gap therebetween; said air gap located adjacent the end of said armature remote from said pilot valve set and said air gap remote from said auxiliary pole piece means;
(h) spring means disposed in said guide hollow biasing said auxiliary pole piece means and said armature means away from each other;
(i) means defining a bleed passage operative for providing limited fluid pressure communication between said inlet passage and said control pressure chamber; and (j) means defining a coil of electrical conductor received over said tubular pole pieces, said coil, of service voltage thereto and flow of electrical current therethrough operable to generate magnetomotive forces in said tubular pole pieces and said auxiliary pole piece means sufficient to move said armature from the closed to the open position, wherein said armature contacts said auxiliary pole piece means and thereafter upon decay of said service voltage to levels below said service voltage, but not less than 40% thereof, said current flow in said coil generates sufficient magnetomotive force in said pole pieces to maintain said armature in contact with said auxiliary pole piece means.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/548,800 US4502661A (en) | 1983-11-04 | 1983-11-04 | Electrically actuated valve assembly |
| US548,800 | 1983-11-04 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1216494A true CA1216494A (en) | 1987-01-13 |
Family
ID=24190445
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000466595A Expired CA1216494A (en) | 1983-11-04 | 1984-10-30 | Electrically actuated valve assembly |
Country Status (2)
| Country | Link |
|---|---|
| US (1) | US4502661A (en) |
| CA (1) | CA1216494A (en) |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3818342A1 (en) * | 1988-05-30 | 1989-12-07 | Hansa Metallwerke Ag | Contactlessly controlled sanitary fitting |
| US4981155A (en) * | 1988-09-30 | 1991-01-01 | Eaton Corporation | Electrically operated valve assembly |
| US5379794A (en) * | 1994-01-25 | 1995-01-10 | Emerson Electric Co. | Gas control valve having polymeric material body combined with thermally responsive gas shutoff valve having metallic body |
| US5622351A (en) * | 1994-05-31 | 1997-04-22 | Daewoo Electronics Co., Ltd. | Water-supply valve of a washing machine |
| AUPM601694A0 (en) * | 1994-05-31 | 1994-06-23 | Technical Components Pty. Ltd. | Low water hammer solenoid operated water valve |
| IT1271264B (en) * | 1994-12-14 | 1997-05-27 | Claber Spa | SOLENOID VALVE FOR IRRIGATION UNITS |
| US5676342A (en) * | 1996-06-17 | 1997-10-14 | Automatic Switch Company | Proportional flow valve with diaphragm pressure member |
| US6290203B1 (en) | 2000-01-18 | 2001-09-18 | Kolze, Inc. | Pilot operated valve assembly |
| US20100019179A1 (en) * | 2008-07-24 | 2010-01-28 | Robertshaw Controls Company | Solenoid for a Pilot Operated Water Valve Having Reduced Copper and Increased Thermal Efficiency |
| KR101664853B1 (en) * | 2010-04-15 | 2016-10-12 | 코웨이 주식회사 | Latch valve and flow control device comprising the same |
| US8500087B2 (en) * | 2010-11-16 | 2013-08-06 | Chi-Han Cheng | Magnetic control valve |
| US10544874B2 (en) * | 2011-01-04 | 2020-01-28 | Robertshaw Controls Company | Coil capture apparatus and pilot operated water valve incorporating same |
| US11112025B2 (en) | 2017-03-30 | 2021-09-07 | Robertshaw Controls Company | Water valve guide tube with integrated weld ring and water valve incorporating same |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2964286A (en) * | 1957-08-23 | 1960-12-13 | I V Pressure Controllers Ltd | Solenoid-operated valve mechanism |
| US3630482A (en) * | 1969-12-17 | 1971-12-28 | Controls Co Of America | Solenoid-operated valve having a plastic solenoid guide tube |
| US3712581A (en) * | 1970-11-02 | 1973-01-23 | Emerson Electric Co | Solenoid combined shading coil and return spring |
| JPS555823Y2 (en) * | 1974-06-29 | 1980-02-09 | ||
| US3943975A (en) * | 1974-11-06 | 1976-03-16 | Emerson Electric Co. | Solenoid operated pilot controlled valve |
| US4262877A (en) * | 1975-05-09 | 1981-04-21 | Lang Gregor L | Solenoid fluid valves |
| US4025887A (en) * | 1975-06-27 | 1977-05-24 | Sperry Rand Corporation | AC solenoid with split housing |
| DE2548774A1 (en) * | 1975-10-31 | 1977-05-05 | Bosch Gmbh Robert | ELECTROMAGNETIC VALVE |
| US4283040A (en) * | 1977-05-13 | 1981-08-11 | Eaton Corporation | Pressure operated pilot control shut-off valve |
| US4222410A (en) * | 1978-06-05 | 1980-09-16 | Turk & Bolte | Outlet fixture for fluid media |
-
1983
- 1983-11-04 US US06/548,800 patent/US4502661A/en not_active Expired - Lifetime
-
1984
- 1984-10-30 CA CA000466595A patent/CA1216494A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| US4502661A (en) | 1985-03-05 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |